Fire alarm



Patented Nov. 14, 1922.

UNITED STATES PATENT OFFICE.

TOMASZ HALAGARDA, CF OMAHA. NEBRASKA.

FIRE ALARM.

Application filed May 5,

vented certain new and use ful Improvements in Fire Alarms, of which the following is a specification. v

This invention relates to thermostats and particularly to those adapted to close an electrical circuit upon encountcrinpy a predetermined degree ot temperature, sometimes called thermostatic alarms.

An object ol this invention is to provide a thermostat of the above, type and one which may be adjusted to close said circuit at any one oi a number ot' predetermined degrees of temperature.

A further object is to provide means 't'ox indicating the extent ot change, and the degree of temperature necessary to etect a closing oi said circuit.

A further object is to provide a thermostat otl the above' type suitable tor use as a tire alarm, and one which is inexpensive to manufacture and install.v small and simple in construction` efficient in oran-ation, and easily adjustable tor particular temperatures.

Referring to the drawings` Fig. 1 repre` sents a side view partly in section oi: the device with the cover shown removed.

Fig. 2 is a top plan view of the device on the line 2-2 of Figure 1.

Similar characters refer to similar parts throughout both views and in whichf l represents a hase carrying an electrical contact 2 fastened thereto as ,hy means ot' screws il, and a spirally curved expansion strip 4, mounted at one end to base 1 as by screws or bolts h'tri p 4 comprises a strip o't topper (S and a strip of steel 7, securely riveted together as at in'. or two othernietals having unequal co-eflicients ot expansion, so that when heat applied, end S) ot the ei;- pansion strip will move in uncoiling direc.- tion, and when heat is removed end 9 will move in the reverse direction.

An electrical Ycontact 2() movable against and away vfrom contact 2 is mounted on vertical rod 1() pivoted to a snppor l! as at 12 and 13, said support being attached to the base as at 25, and carries a threaded lug 14e 1920. Serial No. 379,095.

adapted to receive a screw 15 in swiveled engagement with end 9 ot' the expansion inemher 4. Rod 1U also carries a dial finger 16 adapted to move over a dial 1T niounted on hase 1, and suitably graduated so that the position of iii'ig'er 1G in respect thereto will indicate the amount ot movenient andthe de- ,L'rce ot change in temperature which will eilect a closing ot' electrical contacts 2 and 2U.

lt will be seen that upon the application o lE heat movemento't end 9 of the expansive strip 4 will cause movable contact 2() to move toward contact 2, and will also cause .dial linger 1G to move over dial 17.

By turning: screw 15, contacts Q, and 20 may be set with a variable gap between them and the device set to cause said contacts to meet in response to any one of a number of predetcrmined changes ot temperature, or upon encountering any one oi" a number of predetermined degrees ot' ten'iperature. Contacts and 2() should be insulated from each other and may be connected to a suitable electrical signal system in the usual manner.

A\ lock-nut 21 may be supplied to hold screw 1 5 in adjusted position.

A spider shaped frame 29) may be mounted upon base 1, adapted to receive and retain a cover 24, in protectinpr position over the parts ot the device which cover is preferably constructed ot wire gauze or other heat conducting niaterial to transmit changes of temperature to 'the thermostatic element of the device.

l'l'avinrtluisvdescribed my invention, what i claim is new and desire to secure by Letters Patent ot the United States is ich lows` 1. ln a lire alarmI` a hase, a curved expansion strip on said base coniprising two strips oi" unequal cmeiiicieiits of expansion, a support, a, vertical rod pivotally held by said support. a threaded lutr on said rod, a screw in swivclled engagement with said expansion strip and said lug` a movable anda stationary contact, adapted to he engaged and disengaged by the movement of said expansion strip under changes in temperature.

2. ln a fire alarm. a hase, a spirally curved expansion strip on said base, comprising a of' Sad expansion @wip and said #xi for -sing and sapamimg Said mamme; upon the mow/@mem or said siem srp undef changes in temperature.

En testimony Wheeo have axd my sgmm, n

TMASZ HALAGARDA.,

the and 

